Open AccessArticle
A Simple Approach to Dynamic Optimisation of Flexible Optical Networks with Practical Application
Future Internet 2017, 9(2), 18; doi:10.3390/fi9020018 -
Abstract
This paper provides an initial introduction to, and definition of, the ‘Dynamically Powered Relays for a Flexible Optical Network’ (DPR-FON) problem for opto-electro-optical (OEO) regenerators used in optical networks. In such networks, optical transmission parameters can be varied dynamically as traffic patterns change.
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This paper provides an initial introduction to, and definition of, the ‘Dynamically Powered Relays for a Flexible Optical Network’ (DPR-FON) problem for opto-electro-optical (OEO) regenerators used in optical networks. In such networks, optical transmission parameters can be varied dynamically as traffic patterns change. This will provide different bandwidths, but also change the regeneration limits as a result. To support this flexibility, OEOs (‘relays’) may be switched on and off as required, thus saving power. DPR-FON is shown to be NP-complete; consequently, solving such a dynamic problem in real-time requires a fast heuristic capable of delivering an acceptable approximation to the optimal configuration with low complexity. In this paper, just such an algorithm is developed, implemented, and evaluated against more computationally-demanding alternatives for two known cases. A number of real-world extensions are considered as the paper develops, combining to produce the ‘Generalised Dynamically Powered Relays for a Flexible Optical Network’ (GDPR-FON) problem. This, too, is analysed and an associated fast heuristic proposed, along with an exploration of the further research that is required. Full article
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Open AccessArticle
Towards Rack Utilization in Internet Datacenters: An Approach Based on Dynamic Programming
Future Internet 2017, 9(2), 17; doi:10.3390/fi9020017 -
Abstract
In the datacenter rented to Internet Service Providers (ISPs), the low utilization of racks can seriously affect ISPs’ benefit because the ISPs are charged by “rack per year” rather than servers. Based on our analysis about the utilization data from production systems, we
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In the datacenter rented to Internet Service Providers (ISPs), the low utilization of racks can seriously affect ISPs’ benefit because the ISPs are charged by “rack per year” rather than servers. Based on our analysis about the utilization data from production systems, we find that the over-provisioning of power results in low power utilization, which potentially decreases rack utilization as well as the ISPs’ benefit. To improve the rack utilization, maximizing the number of servers in racks is an effective way. In this paper, we propose a server placement algorithm to minimize the power fragment in a rack. The experimental results show that it can save more than 50% leasing cost (rack utilization improvement) in evaluation. Full article
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Open AccessArticle
Private and Secure Distribution of Targeted Advertisements to Mobile Phones
Future Internet 2017, 9(2), 16; doi:10.3390/fi9020016 -
Abstract
Online Behavioural Advertising (OBA) enables promotion companies to effectively target users with ads that best satisfy their purchasing needs. This is highly beneficial for both vendors and publishers who are the owners of the advertising platforms, such as websites and app developers, but
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Online Behavioural Advertising (OBA) enables promotion companies to effectively target users with ads that best satisfy their purchasing needs. This is highly beneficial for both vendors and publishers who are the owners of the advertising platforms, such as websites and app developers, but at the same time creates a serious privacy threat for users who expose their consumer interests. In this paper, we categorize the available ad-distribution methods and identify their limitations in terms of security, privacy, targeting effectiveness and practicality. We contribute our own system, which utilizes opportunistic networking in order to distribute targeted adverts within a social network. We improve upon previous work by eliminating the need for trust among the users (network nodes) while at the same time achieving low memory and bandwidth overhead, which are inherent problems of many opportunistic networks. Our protocol accomplishes this by identifying similarities between the consumer interests of users and then allows them to share access to the same adverts, which need to be downloaded only once. Although the same ads may be viewed by multiple users, privacy is preserved as the users do not learn each other’s advertising interests. An additional contribution is that malicious users cannot alter the ads in order to spread malicious content, and also, they cannot launch impersonation attacks. Full article
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Open AccessArticle
Assessing OpenStreetMap Data Using Intrinsic Quality Indicators: An Extension to the QGIS Processing Toolbox
Future Internet 2017, 9(2), 15; doi:10.3390/fi9020015 -
Abstract
OpenStreetMap (OSM) is a recent emerging area in computational science. There are several unexplored issues in the quality assessment of OSM. Firstly, researchers are using various established assessment methods by comparing OSM with authoritative dataset. However, these methods are unsuitable to assess OSM
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OpenStreetMap (OSM) is a recent emerging area in computational science. There are several unexplored issues in the quality assessment of OSM. Firstly, researchers are using various established assessment methods by comparing OSM with authoritative dataset. However, these methods are unsuitable to assess OSM data quality in the case of the non-availability of authoritative data. In such a scenario, the intrinsic quality indicators can be used to assess the quality. Secondly, a framework for data assessment specific to different geographic information system (GIS) domains is not available. In this light, the current study presents an extension of the Quantum GIS (QGIS) processing toolbox by using existing functionalities and writing new scripts to handle spatial data. This would enable researchers to assess the completeness of spatial data using intrinsic indicators. The study also proposed a heuristic approach to test the road navigability of OSM data. The developed models are applied on Punjab (India) OSM data. The results suggest that the OSM project in Punjab (India) is progressing at a slow peace, and contributors’ motivation is required to enhance the fitness of data. It is concluded that the scripts developed to provide an intuitive method to assess the OSM data based on quality indicators can be easily utilized for evaluating the fitness-of-use of the data of any region. Full article
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Open AccessArticle
Feature-Based Image Watermarking Algorithm Using SVD and APBT for Copyright Protection
Future Internet 2017, 9(2), 13; doi:10.3390/fi9020013 -
Abstract
Watermarking techniques can be applied in digital images to maintain the authenticity and integrity for copyright protection. In this paper, scale-invariant feature transform (SIFT) is combined with local digital watermarking and a digital watermarking algorithm based on SIFT, singular value decomposition (SVD), and
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Watermarking techniques can be applied in digital images to maintain the authenticity and integrity for copyright protection. In this paper, scale-invariant feature transform (SIFT) is combined with local digital watermarking and a digital watermarking algorithm based on SIFT, singular value decomposition (SVD), and all phase biorthogonal transform (APBT) is proposed. It describes the generation process of the SIFT algorithm in detail and obtains a series of scale-invariant feature points. A large amount of candidate feature points are selected to obtain the neighborhood which can be used to embed the watermark. For these selected feature points, block-based APBT is carried out on their neighborhoods. Moreover, a coefficients matrix of certain APBT coefficients is generated for SVD to embed the encrypted watermark. Experimental results demonstrate that the proposed watermarking algorithm has stronger robustness than some previous schemes. In addition, APBT-based digital watermarking algorithm has good imperceptibility and is more robust to different combinations of attacks, which can be applied for the purpose of copyright protection. Full article
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Open AccessArticle
An Energy Efficient MAC Protocol for Wireless Passive Sensor Networks
Future Internet 2017, 9(2), 14; doi:10.3390/fi9020014 -
Abstract
Medium Access Control (MAC) protocol is one of the key network protocols that ensure Wireless Sensor Networks (WSNs) maintain high performance during communication. MAC protocol design plays an important role in improving the performances of the whole network. First, Wireless Passive Sensor Networks
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Medium Access Control (MAC) protocol is one of the key network protocols that ensure Wireless Sensor Networks (WSNs) maintain high performance during communication. MAC protocol design plays an important role in improving the performances of the whole network. First, Wireless Passive Sensor Networks (WPSNs) and MAC protocols are introduced in this paper. Second, some existing MAC protocols are introduced. Sensor MAC (S-MAC) protocol is analyzed and existing improved backoff algorithms are introduced. A new MAC protocol called Improved Sensor MAC (IS-MAC) is then proposed to solve the problem that the contention window (CW) during carrier sense is fixed in S-MAC protocol. IS-MAC protocol is able to adjust CW in terms of network load, so energy consumption can be decreased. Finally, according to the simulation results on NS2, the proposed protocol has better performance in terms of throughput and energy consumption. Full article
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Open AccessArticle
Spectrum and Energy Efficiency of Uplink Massive MIMO System with D2D Underlay
Future Internet 2017, 9(2), 12; doi:10.3390/fi9020012 -
Abstract
In this paper, both the spectrum efficiency (SE) and the energy efficiency (EE) are investigated for an uplink massive multiple-input multiple-output (MIMO) system coexisting with an underlay device-to-device (D2D) system. The outage probability and the achievable rates of the cellular user equipments (CUEs)
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In this paper, both the spectrum efficiency (SE) and the energy efficiency (EE) are investigated for an uplink massive multiple-input multiple-output (MIMO) system coexisting with an underlay device-to-device (D2D) system. The outage probability and the achievable rates of the cellular user equipments (CUEs) and the D2D link are derived in closed-form, respectively. Constrained by the SE of the D2D link and the CUEs, the EE of the massive MIMO system is maximized by jointly optimizing the transmit power of CUEs and the number of BS antennas. An algorithm with low complexity is proposed to solve the optimization problem. Performance results are provided to validate our derived closed-from results and verify the efficiency of our proposed scheme. Full article
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Open AccessArticle
Participation and Privacy Perception in Virtual Environments: The Role of Sense of Community, Culture and Gender between Italian and Turkish
Future Internet 2017, 9(2), 11; doi:10.3390/fi9020011 -
Abstract
Advancements in information and communication technologies have enhanced our possibilities to communicate worldwide, eliminating borders and making it possible to interact with people coming from other cultures like never happened before. Such powerful tools have brought us to reconsider our concept of privacy
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Advancements in information and communication technologies have enhanced our possibilities to communicate worldwide, eliminating borders and making it possible to interact with people coming from other cultures like never happened before. Such powerful tools have brought us to reconsider our concept of privacy and social involvement in order to make them fit into this wider environment. It is possible to claim that the information and communication technologies (ICT) revolution is changing our world and is having a core role as a mediating factor for social movements (e.g., Arab spring) and political decisions (e.g., Brexit), shaping the world in a faster and shared brand new way. It is then interesting to explore how the perception of this brand new environment (in terms of social engagement, privacy perception and sense of belonging to a community) differs even in similar cultures separated by recent historical reasons. Recent historical events may in effect have shaped a different psychological representation of Participation, Privacy and Sense of Community in ICT environments, determining a different perception of affordances and concerns of these complex behaviors. The aim of this research is to examine the relation between the constructs of Sense of Community, Participation and Privacy compared with culture and gender, considering the changes that have occurred in the last few years with the introduction of the web environment. A questionnaire, including ad hoc created scales for Participation and Privacy, have been administered to 180 participants from Turkey and Italy. In order to highlight the cultural differences in the perception of these two constructs, we have provided a semantic differential to both sub-samples showing interesting outcomes. The results are then discussed while taking into account the recent history of both countries in terms of the widespread of new technologies, political actions and protest movements. Full article
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Open AccessArticle
Decentralized Blind Spectrum Selection in Cognitive Radio Networks Considering Handoff Cost
Future Internet 2017, 9(2), 10; doi:10.3390/fi9020010 -
Abstract
Due to the spectrum varying nature of cognitive radio networks, secondary users are required to perform spectrum handoffs when the spectrum is occupied by primary users, which will lead to a handoff delay. In this paper, based on the multi-armed bandit framework of
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Due to the spectrum varying nature of cognitive radio networks, secondary users are required to perform spectrum handoffs when the spectrum is occupied by primary users, which will lead to a handoff delay. In this paper, based on the multi-armed bandit framework of medium access in decentralized cognitive radio networks, we investigate blind spectrum selection problem of secondary users whose sensing ability of cognitive radio is limited and the channel statistics are a priori unknown, taking the handoff delay as a fixed handoff cost into consideration. In this scenario, secondary users have to make the choice of either staying foregoing spectrum with low availability or handing off to another spectrum with higher availability. We model the problem and investigate the performance of three representative policies, i.e., ρPRE, SL(K), kth-UCB1. The simulation results show that, despite the inclusion of the fixed handoff cost, these policies achieve the same asymptotic performance as that without handoff cost. Moreover, through comparison of these policies, we found the kth-UCB1 policy has better overall performance. Full article
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Open AccessArticle
Improved Recommendations Based on Trust Relationships in Social Networks
Future Internet 2017, 9(1), 9; doi:10.3390/fi9010009 -
Abstract
In order to alleviate the pressure of information overload and enhance consumer satisfaction, personalization recommendation has become increasingly popular in recent years. As a result, various approaches for recommendation have been proposed in the past few years. However, traditional recommendation methods are still
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In order to alleviate the pressure of information overload and enhance consumer satisfaction, personalization recommendation has become increasingly popular in recent years. As a result, various approaches for recommendation have been proposed in the past few years. However, traditional recommendation methods are still troubled with typical issues such as cold start, sparsity, and low accuracy. To address these problems, this paper proposed an improved recommendation method based on trust relationships in social networks to improve the performance of recommendations. In particular, we define trust relationship afresh and consider several representative factors in the formalization of trust relationships. To verify the proposed approach comprehensively, this paper conducted experiments in three ways. The experimental results show that our proposed approach leads to a substantial increase in prediction accuracy and is very helpful in dealing with cold start and sparsity. Full article
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Open AccessArticle
Designing a Softwarized Network Deployed on a Fleet of Drones for Rural Zone Monitoring
Future Internet 2017, 9(1), 8; doi:10.3390/fi9010008 -
Abstract
In the last decade, the differences in the information communication technology (ICT) infrastructures between urban and rural areas have registered a tremendous increase. ICT infrastructures could strongly help rural communities where many operations are time consuming, labor-intensive and expensive due to limited access
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In the last decade, the differences in the information communication technology (ICT) infrastructures between urban and rural areas have registered a tremendous increase. ICT infrastructures could strongly help rural communities where many operations are time consuming, labor-intensive and expensive due to limited access and large distances to cover. One of the most attractive solutions, which is widely recognized as promising for filling this gap, is the use of drone fleets. In this context, this paper proposes a video monitoring platform as a service (VMPaaS) for wide rural areas not covered by Internet access. The platform is realized with a Software-Defined Network (SDN)/Network Functions Virtualization (NFV)-based flying ad-hoc network (FANET), whose target is providing a flexible and dynamic connectivity backbone, and a set of drones equipped with high-resolution cameras, each transmitting a video stream of a portion of the considered area. After describing the architecture of the proposed platform, service chains to realize the video delivery service are described, and an analytical model is defined to evaluate the computational load of the platform nodes in such a way so as to allow the network orchestrator to decide the backbone drones where running the virtual functions, and the relative resources to be allocated. Numerical analysis is carried out in a case study. Full article
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Open AccessArticle
An Adaptive Privacy Protection Method for Smart Home Environments Using Supervised Learning
Future Internet 2017, 9(1), 7; doi:10.3390/fi9010007 -
Abstract
In recent years, smart home technologies have started to be widely used, bringing a great deal of convenience to people’s daily lives. At the same time, privacy issues have become particularly prominent. Traditional encryption methods can no longer meet the needs of privacy
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In recent years, smart home technologies have started to be widely used, bringing a great deal of convenience to people’s daily lives. At the same time, privacy issues have become particularly prominent. Traditional encryption methods can no longer meet the needs of privacy protection in smart home applications, since attacks can be launched even without the need for access to the cipher. Rather, attacks can be successfully realized through analyzing the frequency of radio signals, as well as the timestamp series, so that the daily activities of the residents in the smart home can be learnt. Such types of attacks can achieve a very high success rate, making them a great threat to users’ privacy. In this paper, we propose an adaptive method based on sample data analysis and supervised learning (SDASL), to hide the patterns of daily routines of residents that would adapt to dynamically changing network loads. Compared to some existing solutions, our proposed method exhibits advantages such as low energy consumption, low latency, strong adaptability, and effective privacy protection. Full article
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Open AccessArticle
Automatic Detection of Online Recruitment Frauds: Characteristics, Methods, and a Public Dataset
Future Internet 2017, 9(1), 6; doi:10.3390/fi9010006 -
Abstract
The critical process of hiring has relatively recently been ported to the cloud. Specifically, the automated systems responsible for completing the recruitment of new employees in an online fashion, aim to make the hiring process more immediate, accurate and cost-efficient. However, the online
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The critical process of hiring has relatively recently been ported to the cloud. Specifically, the automated systems responsible for completing the recruitment of new employees in an online fashion, aim to make the hiring process more immediate, accurate and cost-efficient. However, the online exposure of such traditional business procedures has introduced new points of failure that may lead to privacy loss for applicants and harm the reputation of organizations. So far, the most common case of Online Recruitment Frauds (ORF), is employment scam. Unlike relevant online fraud problems, the tackling of ORF has not yet received the proper attention, remaining largely unexplored until now. Responding to this need, the work at hand defines and describes the characteristics of this severe and timely novel cyber security research topic. At the same time, it contributes and evaluates the first to our knowledge publicly available dataset of 17,880 annotated job ads, retrieved from the use of a real-life system. Full article
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Open AccessArticle
Construction Management Risk System (CMRS) for Construction Management (CM) Firms
Future Internet 2017, 9(1), 5; doi:10.3390/fi9010005 -
Abstract
After the global financial crisis of 2008, the need for risk management arose because it was necessary to minimize the losses in construction management (CM) firms. This was caused by a decreased amount of orders in the Korean CM market, which intensified order
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After the global financial crisis of 2008, the need for risk management arose because it was necessary to minimize the losses in construction management (CM) firms. This was caused by a decreased amount of orders in the Korean CM market, which intensified order competition between companies. However, research results revealed that risks were not being systematically managed owing to the absence of risk management systems. Thus, it was concluded that it was necessary to develop standard operating systems and implement risk management systems in order to manage risks effectively. Therefore, the purpose of this study was to develop a construction risk management system (CRMS) for systematically managing risks. For this purpose, the field operation managers of CM firms were interviewed and surveyed in order to define risk factors. Upon this, a risk assessment priority analysis was performed. Finally, a risk management system that comprised seven modules and 20 sub-modules and was capable of responding systematically to risks was proposed. Furthermore, the effectiveness of this system was verified through on-site inspection. This system allows early response to risks, accountability verification and immediate response to legal disputes with clients by managing risk records. Full article
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Open AccessArticle
A Point of View on New Education for Smart Citizenship
Future Internet 2017, 9(1), 4; doi:10.3390/fi9010004 -
Abstract
Smart cities and intelligent communities have an ever-growing demand for specialized smart services, applications, and research-driven innovation. Knowledge of users’ profiles, behavior, and preferences are a potentially dangerous side effect of smart services. Citizens are usually not aware of the knowledge bases generated
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Smart cities and intelligent communities have an ever-growing demand for specialized smart services, applications, and research-driven innovation. Knowledge of users’ profiles, behavior, and preferences are a potentially dangerous side effect of smart services. Citizens are usually not aware of the knowledge bases generated by the IT services they use: this dimension of the contemporary and digital era sheds new light on the elements concerning the concept of citizenship itself, as it affects dimensions like freedom and privacy. This paper addresses this issue from an education system perspective, and advances a non-technical methodology for being aware and recognizing knowledge bases generated by user-service interaction. Starting from narratives, developed in natural language by unskilled smart service users about their experience, the proposed method advances an original methodology, which is identified in the conceptual models derived from these narratives, a bridge towards a deeper understanding of the informative implications of their behavior. The proposal; which is iterative and scalable; has been tested on the field and some examples of lesson contents are presented and discussed. Full article
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Open AccessFeature PaperArticle
Towards Incidence Management in 5G Based on Situational Awareness
Future Internet 2017, 9(1), 3; doi:10.3390/fi9010003 -
Abstract
The fifth generation mobile network, or 5G, moves towards bringing solutions to deploying faster networks, with hundreds of thousands of simultaneous connections and massive data transfer. For this purpose, several emerging technologies are implemented, resulting in virtualization and self-organization of most of their
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The fifth generation mobile network, or 5G, moves towards bringing solutions to deploying faster networks, with hundreds of thousands of simultaneous connections and massive data transfer. For this purpose, several emerging technologies are implemented, resulting in virtualization and self-organization of most of their components, which raises important challenges related to safety. In order to contribute to their resolution, this paper proposes a novel architecture for incident management on 5G. The approach combines the conventional risk management schemes with the Endsley Situational Awareness model, thus improving effectiveness in different aspects, among them the ability to adapt to complex and dynamical monitoring environments, and countermeasure tracking or the role of context when decision-making. The proposal takes into account all layers for information processing in 5G mobile networks, ranging from infrastructure to the actuators responsible for deploying corrective measures. Full article
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Open AccessEditorial
Acknowledgement to Reviewers of Future Internet in 2016
Future Internet 2017, 9(1), 2; doi:10.3390/fi9010002 -
Abstract The editors of Future Internet would like to express their sincere gratitude to the following reviewers for assessing manuscripts in 2016.[...] Full article
Open AccessFeature PaperArticle
Key Technologies in the Context of Future Networks: Operational and Management Requirements
Future Internet 2017, 9(1), 1; doi:10.3390/fi9010001 -
Abstract
The concept of Future Networks is based on the premise that current infrastructures require enhanced control, service customization, self-organization and self-management capabilities to meet the new needs in a connected society, especially of mobile users. In order to provide a high-performance mobile system,
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The concept of Future Networks is based on the premise that current infrastructures require enhanced control, service customization, self-organization and self-management capabilities to meet the new needs in a connected society, especially of mobile users. In order to provide a high-performance mobile system, three main fields must be improved: radio, network, and operation and management. In particular, operation and management capabilities are intended to enable business agility and operational sustainability, where the addition of new services does not imply an excessive increase in capital or operational expenditures. In this context, a set of key-enabled technologies have emerged in order to aid in this field. Concepts such as Software Defined Network (SDN), Network Function Virtualization (NFV) and Self-Organized Networks (SON) are pushing traditional systems towards the next 5G network generation.This paper presents an overview of the current status of these promising technologies and ongoing works to fulfill the operational and management requirements of mobile infrastructures. This work also details the use cases and the challenges, taking into account not only SDN, NFV, cloud computing and SON but also other paradigms. Full article
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Open AccessArticle
Designing and Implementing Weather Generators as Web Services
Future Internet 2016, 8(4), 55; doi:10.3390/fi8040055 -
Abstract
Climate and weather realizations are essential inputs for simulating crop growth and yields to analyze the risks associated with future conditions. To simplify the procedure of generating weather realizations and make them available over the Internet, we implemented novel mechanisms for providing weather
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Climate and weather realizations are essential inputs for simulating crop growth and yields to analyze the risks associated with future conditions. To simplify the procedure of generating weather realizations and make them available over the Internet, we implemented novel mechanisms for providing weather generators as web services, as well as a mechanism for sharing identical weather realizations given a climatological information. A web service for preparing long-term climate data was implemented based on an international standard, Sensor Observation Service (SOS). The weather generator services, which are the core components of the framework, analyze climatological data, and can take seasonal climate forecasts as inputs for generating weather realizations. The generated weather realizations are encoded in a standard format, which are ready for use to crop modeling. All outputs are generated in SOS standard, which broadens the extent of data sharing and interoperability with other sectoral applications, e.g., water resources management. These services facilitate the development of other applications requiring input weather realizations, as these can be obtained easily by just calling the service. The workload of analysts related to data preparation and handling of legacy weather generator programs can be reduced. The architectural design and implementation presented here can be used as a prototype for constructing further services on top of an interoperable sensor network system. Full article
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Open AccessArticle
A Novel Multi-Focus Image Fusion Method Based on Stochastic Coordinate Coding and Local Density Peaks Clustering
Future Internet 2016, 8(4), 53; doi:10.3390/fi8040053 -
Abstract
The multi-focus image fusion method is used in image processing to generate all-focus images that have large depth of field (DOF) based on original multi-focus images. Different approaches have been used in the spatial and transform domain to fuse multi-focus images. As one
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The multi-focus image fusion method is used in image processing to generate all-focus images that have large depth of field (DOF) based on original multi-focus images. Different approaches have been used in the spatial and transform domain to fuse multi-focus images. As one of the most popular image processing methods, dictionary-learning-based spare representation achieves great performance in multi-focus image fusion. Most of the existing dictionary-learning-based multi-focus image fusion methods directly use the whole source images for dictionary learning. However, it incurs a high error rate and high computation cost in dictionary learning process by using the whole source images. This paper proposes a novel stochastic coordinate coding-based image fusion framework integrated with local density peaks. The proposed multi-focus image fusion method consists of three steps. First, source images are split into small image patches, then the split image patches are classified into a few groups by local density peaks clustering. Next, the grouped image patches are used for sub-dictionary learning by stochastic coordinate coding. The trained sub-dictionaries are combined into a dictionary for sparse representation. Finally, the simultaneous orthogonal matching pursuit (SOMP) algorithm is used to carry out sparse representation. After the three steps, the obtained sparse coefficients are fused following the max L1-norm rule. The fused coefficients are inversely transformed to an image by using the learned dictionary. The results and analyses of comparison experiments demonstrate that fused images of the proposed method have higher qualities than existing state-of-the-art methods. Full article
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